Why does your ESC overheat (Read This To Prevent Damage)


Heat is one variable that can damage your expensive RC vehicle’s parts since an overly high temperature can cause decreased performance.

The ESC is one component that can easily overheat when run under the wrong conditions and when it involves repairs, they are pretty expensive.

If you don’t want to incur additional expenses that will take a toll on your finances, you need to learn to keep your ESC in the right temperatures. 

This article details every information you’ll need on why and what causes ESC to overheat and how to keep them at cool temps. 

The Cause For RC ESC to Overheat

If you find that your RC car ESC is frequently overheating, you need to check that the ESC is not under-geared, over-geared, poorly soldered or running at high voltages. 

Any RC car’s Electronic Speed Control (ESC) will get hot if the system works under high load and after the model has completely drained a battery pack. A hot ESC could often result from the driving style, especially in a high resistance environment filled with mud, water, and tall grass.

Other times, the problem could be from under gearing, soldering, and voltage issues, making the RC car’s temperature levels increase significantly. 

Why does under gearing overheat the ESC?

In most cases, when an ESC is under-geared, it goes into thermal shutdown to protect the electronics.

A hot motor plus a cool ESC will mean that your RC car is under-geared, which will also tell you’re running at too high a voltage and amperage, which may overheat the ESC.

The major cause of under gearing of an ESC is when the pinon is too small or you have an overly large spur gear. On the other hand, your pinion and spur gear may mesh too tight, causing friction and resistance issues that make them heat up.

Your ESC will function well and remain cool when you get the perfect gear ratio they can work with. 

What is the right gearing to prevent overheating?

The best way to prevent under gearing of the ESC is to get the gear mesh correctly. The ESC overheats due to too tight a gear mesh, so loosening the gear mesh appropriately. 

Make sure that the gear mesh is neither too loose nor too tight. 

Can the soldering cause overheating to your ESC?

A poorly soldered job that doesn’t melt but breaks off can cause the ESC to overheat. 

Plus, if you solder the ESCs wire for too long and let the heat soak into the ESC, it could cause the ESC to overheat. It’s always best to solder the cables for not more than 10 seconds, preferably around six seconds.
Poor soldering could also cause overheating at the solder joint. 

How can the motor cause overheating of the ESC?

When your RC motor overheats, it doesn’t just affect the performance of the RC car but also shortens and damages the ESC.  

A motor can cause the ESC to overheat when it pulls lots of electrical current through the small wires on the ESC to operate properly. This doesn’t frequently happen since most ESCs can perfectly handle the motors.
However, the ESC will overheat when it does happen because it is not built to withstand any level of power that flows through it. 

Can the batteries cause overheating to the ESC?

Yes, the batteries can burn out your ESC, especially when the current and battery voltage is too high. 

The current tells the total amperage of your RC car. Too many amps passing through your ESC can cause it to get hot, and when the current gets too high, it will cause your ESC to fail. Usually, a high current is generated when the battery gets shortened during operation. It can also be a result of an overly hot motor. 

On the other hand, the voltage accompanies the amperage of an RC car since it determines how fast the vehicle moves. Regardless of its function in your RC’s performance, the ESC will always expect a certain amount of voltage at a time.
If the voltage exceeds what it can hold, it causes the ESC to be damaged or overheat. 

Can lack of ventilation cause ESC to overheat? 

The ESC can also burn up when it does not get the appropriate cooling. 

Most people fail to understand that their RC electrical components can get extremely hot, especially when used at their maximum capacity. For example, if you’re using an RC car on high-impact terrains filled with sand and water, you risk using the ESC at its full power. This means that the ESC will become extremely hot and overheat without a cooling solution. 

If you are a hobbyist that likes to take your RC to the limit, it’s advised to get a cooling agent such as a fan or heatsink.

Should you replace an ESC that’s overheating? 

You don’t necessarily have to change an ESC that’s overheating. 

All you need do is carry out emergency maintenance or leave the motor to rest for some time before running them again. However, if you find that the ESC is damaged due to excessive heat, you may have to replace it. 

If the ESC is overheating during operation, stop your RC vehicle and remove the RC body to allow air to enter the vehicle and cool. Once the RC vehicle is at a lower temperature, carry out a test run to ensure the ESC is still functioning. If the ESC does not show any readings, it could mean that it has been damaged. 

Do ESCs have an overheat protection?

An ESC does have an overheat protection, which is often a thermal protection device that helps you identify when your ESC burns at an overly high temperature and keep the temperature cool. 

When your ESC gets too hot, this device allows the ESC shut down by itself to prevent it from being damaged. 

How should you keep your ESC cool?

To keep your ESC running coolly at optimal temperature without worrying about them overheating easily, you could either get cooling devices like fan and heat sinks for them or cut out some sections of their body to allow good ventilation.
If the ESC heats due to under gearing, make sure to set the gear mesh not too tight and not too loose. 

First, consider getting cooling devices like heat sinks and fan if your RC vehicle does not come with one. These devices will help you dissipate heat without stress. Heat sinks are even small and will effectively draw out the heat than a fan. 

Alternatively, cut out some small sections on the RC car body to increase airflow. If you own an RC truck, cut the window and the rear a little more, so it is a little higher. If it’s a buggy you have, cut off the tail after the rear clip hole. Another method you want to consider is to mount the ESC on the Rear Shock tower and not the bottom; this way, your ESC gets the much-needed ventilation it needs to function well. 

Do I need a fan on my ESC?

When you install a fan on your ESC, it increases its overall performance. In fact, your ESC can even run up to 15 degrees cooler when you attach a fan to it. However, you need to know which fan size and voltage it allows. 

Make sure to measure the fan’s diameter, then check that the voltage is higher than that of your ESC. Also, make sure that you select a fan with the right connecting plugs to your ESC. 

What can happen to an overheating ESC?

Understand that the ESC produces nearly as much heat as a motor. However, it will fail almost instantly if its temperature limit is exceeded. 

In short, if the ESC overheats due to too high amperage, voltage, under gearing, and poor ventilation, the ESC will completely fail and require replacement


An ESC will often overheat if the motor tries to pull too much current from the ESC, or when the current and voltage are too high, the ESC lacks proper ventilation or a poorly soldered job. In essence, it overheats when it is being misused. You need to ensure that the ESC is used in the right conditions while getting enough air to ensure it functions optimally. 

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